Method of providing stranded structures with fittings



Nov. 22, 1938. o. J. BRATZ 2,137,712

METHOD OF PROVIDING STRANDED STRUCTURES WITH mwwmes Filed April 9, 1955 AVIIVIIAWIIY INVENTQR 0770 q. 72 a B M ATTORNEY fjijil Patented Nov. 22, 1938 PATENT OFFICE METHOD OF PROVIDING STRANDED STRUC- TURES WITH FITTINGS Otto J. Bratz, Adrian, Mich, assignor, by'mesne assignm ents, ,to American Chain & Cable .Com-

pany, Inc., a corporation of New York Application April 9, 1935, Serial No. 15,405

23 Claims.

This invention relates to a method of providing flexible stranded wire structures with reinforcements or fittings and is described with particularity as to its application in providing the ends of a flexible helically coiled wire tubular casing with means for preventing uncoiling or spreading which means constitutes a sleeve or ferrule or attachment member for the end of the casing.

It is common practice to make coiled wire tubing primarily in continuous form and then to cut the tubing into desired lengths. Heretofore, it has been necessary to provide auxiliary clamping means to prevent the severed wires from springing and uncoiling until they could be secured permanently by a sleeve, ferrule or other bindin means. My invention has for an object the provision of a method which dispenses with such auxiliary clamping means and simplifies the method of manufacturing flexible wire casings by providing a binding which may be applied at predetermined spaced points on the casing before the casing is severed and which is of such a character that it may be converted into a ferrule or its equivalent by a swedging operation either before or after the severing operation. e

Other objects and advantages of my improved method will appear from the following description of my method with reference to a disclosure of several preferred embodiments of helically coiled wire tubular casings produced by my method, and thereafter the novelty and scope of my invention will be pointed out in the claims.

In the accompanying drawing:

Figure 1 is a view in side elevation and partly in section of one end of a stranded wire casing with a binding or reinforcement applied thereto in accordance with my method and before swedging;

Fig. 2 is a view in side elevation of both ends of a stranded wire casing with reinforcements applied thereto and swedged thereon in accordance with my method, one end of the casing being partly broken away to show structural details;

Fig. 3 is a view in cross-section taken substantially on the line 3-3 of Fig. 2;

Figs. 4 and 4a are plan and end views respectively of a reinforcement strip, illustrating the conformation of the inner face of the strip;

Fig. 5 is a view in side elevation and partly in section of one end of a stranded wire casing with a reinforcement applied thereto in accordance with my method, such reinforcement being of different section from that shown inFig. 2;

Figs. 6 and 6a are plan and end views respectively of the inner face of the reinforcement strip employed in the structure shown in Fig. 5;

Fig. 7 is a view in side elevation and partly in section of one end of a stranded wire casing reinforced with a metallic strip of different section from that shown in Figs. 2 and 5 and with a metallic sleeve swedged upon the reinforcement, in accordance with my method;

' Figs. 8 and 8a are plan and end views respectively of the reinforcement strip shown in Fig. 7;

Fig. 9 is a view in side elevation and partly in section of one end of a stranded wire casing with reinforcement applied thereto and with one-half of a split clamp engaging such reinforced end of the casing, in accordance with my method;.

Fig. 10 is an end view looking from the left hand side of Fig. 9 with both halves of the clamp applied to the casing; and

Figs. 11 and 12 are fragmental views in side elevation and partly in section of two other forms of flexible casing with a reinforcement swedged thereon in accordance with my method.

The flexible wire casing shown in Figs. 1 and 2 is of standard construction and comprises an inner layer l5 consisting of a helix of flat wire, the convolutions of the helix being slightly spaced apart so as to permit of flexing the helix about its axis. A second layer I6 which is applied directly upon the helix 15 comprises a series of contiguous wires coiled with a long pitch. An outer helix l1 serves to bind the wires of the second layer so that when the structure is flexed the wires of the second layer will be constrained to slide lengthwise relatively to each other, but will be maintained at all times in close contact. The outer helix I'l serves merely to retain the wires of the second layer l8 and consequently the convolutions of this helix are widely spaced apart.

To hold the wires of the different layers in place and prevent them from unwinding, I apply a binding or reinforcement strip ll! of the character shown in detail in Figs. 4 and 4a. The binding strip I8 is formed with a central groove or recess l9 adapted to embrace the wire of the outer helix H. The width of the stripis slightly less than the center to center spacing of the convolutions of helix H. The strip l8 when applied to the casing is wound in the same direc tion and with the same pitch as the helix IT, as shown in Fig. 1. The strip may also be knurled or formed with transverse depressions 20 to regis ter with and fit upon the wires of the second layer 16.

As a strip I8 is wound upon the casing it is preferably preformed to a smaller diameter than the outside diameter of the: casing so that it will tightly hug the casing. 'Such binding or reinspreading. The hold of the binding strip will be increased if the parts are so proportioned asto effect engagement of the transverse depressions 20 with the wires of layer l6.

Each end of the casing is now subjected to a swedging operation, an arbor 2| being inserted.

in the end under treatment. The swedging operation compresses the binding from thecondition illustrated in Fig. 1 to that illustrated in Fig. 2, in which it will be observed that the binding strip is forced into intimate contact with the casing, substantially enveloping the wire of helix l1 and being to a certain extent molded upon the wires of the second layer I6. The swedging operation also causes the helix I! to be partly embedded in corrugations of layer l6, thereby tying the wires of layer l6 together, and since the helix I1 is also embedded in the binding strip l8 the latter is thus firmly anchored to the layer I6 as well. It will also be observed from an inspection of Fig. 2 (which shows the finished casing after the arbor 2| has been withdrawn) that in the swedging operation the strip I8 is spread so that adjacent convolutions are in tight contact and the result is a substantially continuous sleeve forming a reinforcement on the end of the casing. This sleeve is preferably of such thickness that an annular groove 22 may be formed therein for attachment purposes. Also the sleeve may be threaded, if desired, as shown at 23 (Fig. 5).

The structure shown in Figs. 5, 6 and 6a differs from that already described mainly ii that a binding strip of different cross-section is employed. This binding; strip which is indicated by the reference numeral 25 is of the same width as the binding strip |8 but instead of having a central groove is formed with two quarter-circle grooves 26 along each margin which are adapted to engage adjacent convolutions of the layer Between the grooves 26 the inner face of the strip is formed with depressions 21 adapted to fit upon the wires of layer |6. Fig. 5 shows the strip after it has been applied to the casing and swedged thereon. As explained above, this reinforcement may be formed with threads 23 for attachment purposes, or, if desired, it may be formed with an attachment groove 22. when the binding strip is swedged upon the casing the convolutions of layer H are embedded in the binding strip at the junction between adjacent convolutions of the strip. In this case, as in that described above, the swedging operation serves to cause partial embedment of layer |1 into layer l6 and also partial embedment of layer l6 and binding strip 25 so that the parts are all rigidly united.

In the construction shown in Figs. '7, 8 and 8a.

is rounded, as shown at 33. The groove 3| is adapted to receive the wire of layer l1 and transverse depressions 32 in the face of the strip are adapted to receive the wires of layer l6. After In Fig. '7 I show still another form of attachment fitting. This consists of a sleeve 34 which is fitted over the binding 30 and then is swedged thereon. The sleeve is thus made fast to the reinforcement 30 and hence to the casing by frictional engagement therewith and also by partial embedment. Such embedment is due to the fact that the strip is formed with a rounded edge 33 so as to provide a groove between adjacent convolutions of the strip 36 into which the metal of the sleeve 34 is forced by the swedging operation. The sleeve 34 may be provided with an annular groove 35 for attachment purposes.

Another means of attaching the casing to a fixed support is shown in Figs. 9 and 10. The structure of the casing and reinforcement corresponds to that shown in Figs. 1 and 2. The fixture to which the casing is attached consists of a clamp comprising a member 38 and a member 39. This clamp has va bore 40 formed between the members which is of the same diameter as the inside diameter of the casing at the point where it has been swedged. The bore has an enlargement 4| to receive the casing, and the latter is clamped between the members 33 and 39 by means of bolts 42. The casing serves usually as a guide for a rotary and/or sliding power transmitting element and there is the danger that the inner layer may'present a sharp or jagged wire end which will engage said element, fraying the casing or causing a serious jam. To avoid this I bevel the inner layer of the casing. as indicated at 43, and provide an annular flange 44 on the members 38 and 33 at the junction of bore 40 and enlargement 4|, this flange being beveled to fit the bevel 43. Thus, the end of the inner layer is bound and held in place by the flange 44.

Fig. 11 shows one end of the piece of easing made of two helices of wire 45 and 46 respectively which are of triangular cross-section with the base ofthe triangle of wire 45 forming the inner face of the casing and the base of the triangle of wire 46 forming the outer face of the casing. Upon this casing is wrapped a binding strip 41 which is of rectangular section. The wires 45 and 46 form right-hand helices whereas the strip 41 forms a left hand helix so that the joints .between successive convolutions of the strip 41 are disposed transversely to the joints between the convolutions of the helix formed from wire 46. The casing and binding strip are subjected to a -swedging operation which binds the strip 41 tightly to the casing, forcing it into the crevices formed between successive convolutions of the helix formed from wire 46. This serves to bind the strip 41 upon the casing and to form a substantially rigid sleeve portion at the end of the casing. While I prefer to reverse the binding with respect to that of the helices formed from wire 45 and 46 I do not wish to limit myself to this arrangement, since itwill be obvious that by using a binding strip which is much wider than the wire 46, such binding strip must be wound with a greater pitch angle if adjacent convolutions are contiguous and consequently the joint between successive convolutions of the strip 41 cannot coincide with the joint between convolutions of wire 46 but must traverse such 7 fore wrapping to fit the surface forming the ribbon during the wrapping to hug a strip ti which may be of the same section as strip 4'! and as in the structure shown in Fig. 11, the lay of the strip 5| is preferably although not necessarilyreversed with respect to that of the helix 5!]. The casing and binding strip 5| are subjected to a swedging operation which forces the strip 5| into the crevices between adjacent convolutions of the helix 50, thus binding said convolutions and forming a rigid. sleeve at the end of the casing. V

While I have described my method in connection with a disclosure of several forms of coiled wire casings, binding strips and end fittings produced thereby, it is to be understood that this disclosure and the specific description thereof and of my method as applied thereto, are to be taken merely as illustrative and not limitative of the method and its application to stranded structures generally, and that I reserve the right to vary my method and apply it to produce diiferent forms of tubular casings, conduits, shaftings', etc., without departing from the spirit andscope of my invention as clearly set forth in the following claims. In the claims, I employ the terms tubular caslng,"- casing, coil and helical coil in their broad sense toinclude all,equivalents to which my method may be applied.

I claim:

1. The methodof producing flexible tubular casings from a continuous wire coil, which includes the steps of Wrapping the wire coil with a metal ribbon at separate predetermined points on the coil, severing the coil at such points by cuttingthrough the ribbon and the coil so as to form a plurality of tubular casings each having a metal ribbon binding at each end thereof, and swedging the ribbon upon the coil at each end of the casing.

2. The method of making flexible tubular casings froma continuous wire coil, which includes the steps of wrapping the wire coil with a metal ribbon at separate predetermined points on the coil, contouring the inner face of the ribbon before wrapping to fit the surface of the coil, severing the coil at such points by cutting through the ribbon and the coil so as to form a plurality of tubular casings each having a metal ribbon binding at each end thereof, and swedging the ribbon on the coil at each end of the casing.

3. The method of making flexible tubular casings from a continuous wire coil, which includes the steps of wrapping the wire coil with a metal ribbon at separate predetermined points on the coil, contouring the inner face of the ribbon beof the coil, prethe coil, severing the coil at such points by cutting through the ribbon and the coil so as to form a plurality of tubular casings each having a metal ribbon binding at each end thereof, and swedging the ribbon on the coil at each end of the casing.

4. The method of making flexible tubular casings from a continuous wire coil structure composed'of a plurality of layers, the outer layer consisting of an open coil, which includes the steps of wrapping a metal strip upon the coil structure at separate predeterminedpoints thereon, forming a groove in the strip before wrapping to plurality of tubular casings each a longitudinal recess to receive the Wire of receive the wire of said open coil, severing the coil structure at said points by cutting through the strip and the coil structure so as to form a having a metal strip binding at each end thereof, and swedging the strip on the tubularstructure at each end of the casing.

coil structure, severing the coil structure at said 1 points by cutting through the strip and the coil I structure so as to form a pluraliy of tubular casings each having a metal strip binding at each end thereof, and swedging the strip on the tubular structure at each end of the casing.

6. The-method of making flexible tubular casings from a continuous wire coil structure composed of a plurality of layers, the outer layer consisting of an open coil of reverse lay with respect to that of the next adjacent layer, which includes the steps of wrapping a metal strip upon the coil structure at separate predetermined points thereon, forming the metal, strip before winding with a longitudinal recess to receive the wire of said open coil and with transverse recesses to fit over the convolutions of said next adjacent layer, severing the coil structure at said structure so as to form a pluralityiof tubular casings each having a metal strip binding at each end thereof, and swedging the binding on the tubular structure at each end of the casing.

7. The method of making flexible tubular casings from a continuous wire coil structure composed of a plurality of layers with the outer layer consisting of an open coil, which includes the steps of forming a bindingstrip of a width slightly less than the center to center spacing of the convolutions of said open .coil and with a longitudinal recess to receive the wire of said open coil, wrapping the strip upon the coil structure at separate predetermined points thereon with the wire of said open coil in said recess, severing the coil structure at said points by cutting the strip and the coil structure so as to form a I plurality of tubular casings each having a metal wire and strip and spread the turns of the strip into mutually contiguous relation.

8. The method of making flexible tubular casings from a continuous wire coil structure composed of a plurality of layers with the outer layer consisting of an open coil, which includes the steps of forming a binding strip of a width slightly less than the center to center spacing of the convolutions of said open coil and with said open coil, wrapping the strip upon the coil structureat separate predetermined points thereon with the wire of said open coil in "said recess, preforming the strip as it is wrapped to hub the coil structure, severing the coil structure at said points by cutting the strip and the coil structure so as to each having thereof, and

structure at each end of the casing to effect mutual embedment of the wire and strip and spread the turns of the strip into mutually contiguous relation.

9. The method of forming flexible tubular casings from a continuous wire coil structure composed of a plurality of layers with the outer layer consisting of an open coil, which includes the steps of preparing a metal strip of a width slightly less than the center to center spacing of the convolutions of said outer coil and forming the strip with a recess along each margin thereof, winding the strip at predetermined points upon the coil structure between the convolutions of said open coil and with said con-- volutions'partly embraced in said recesses, severing the coil structure at said points by cutting through the strip and the coil structure so as to form a plurality of tubular casings each having a metal strip binding at. each end thereof, and swedgingthe strip on the tubular structure at each end of the casing so as to spread the .convolutions of the strip into mutually contiguous relation and completely envelopthe convolutions of said open coil and also so as to embed the strip in the layer next adjacent said open coil.

10. The method of binding an end of a coiled wire casing which includes the steps of wrapping a metal strip helicallyabout the casing at said end, contouring the inner face of the strip before wrapping so that it will fit upon the coiled wire 'surface of the casing, and swedging the wrap-- ping upon the casing so as to form a ferrule thereon.

11. The method of binding an end of a coiled wire casing which includes the steps of wrapping a metal strip helically about the casing at said end, contouring the inner face of the strip before wrapping so that it will fit upon the coiled wire surface of the casing, preforming the strip as it is being wrapped about the casingso that it will hug said casing closely, andswedging the wrapping upon the casing so as to form a ferrule thereon. I r

12. The method of binding an' end ofa' tubular casing comprising at least one coil of wire. whieh includes the steps of wrapping a metal-\sttip helically upon the coil 'at said end but witlr'a reverse lay with respect to that of said coil, and swedging the wrapping upon "the casing 'to force the material of the wrapping'into the in.

terstices between theconvolutions of said coil and form a ferrule on the casing.

13. The method of binding an end of a tubular coiled wire casing, which includes the steps of wrapping a metal strip helically upon the coiled wire casing at said end but with a reverse lay with respect to that of said coiled wire casing,- transversely grooving the inner face of the strip before wrapping so that it will fit upon the coiled wire surface of the casing, and swedging the wrapping uponthe casing to force the material.

of the wrapping into the interstices between the convolutions of said coiled wire casing and form a ferrule on the'casing.

14. The method of producing desired lengths of stranded wire structures and reinforcing the ends thereof, which consists in wrapping wire bindings on a continuous length of stranded wire'. structure at points spaced at distances corresponding to said lengths, and of sufficient inherent strength to preserve the integrity of the stranded wire structure when severed at said points, severing the wire bindings and stranded wire structure at such points to form a plurality of such stranded structures of desired length each having a wire binding on each end there-- such desired lengths of stranded wire structures each having a wire binding on each end thereof.

16. ,The method of producing desired lengths of stranded wire structures provided with end fittings, which consists'in constricting upon a continuous length of a stranded wire structure, at points spaced at distances corresponding to such lengths, members of sufiicient inherent strength to preserve the integrity of said stranded wire structure when severed, severing the members and stranded wire structure at such points to form a plurality of such stranded wire structures, each having a constricting member on each end thereof, and swedging said members on such stranded wire structures to form end fittings.

1'7. The method of producing desired lengths of coiled wire structure's provided with end fittings, which consists in constricting, at points on a continuous length of a coiled-wire structure spaced at distances corresponding to such lengths, members of sufilcient inherent strength to prevent uncoiling of said coiled wire structure when severed, severing the members and coiled wire form a plurality of structure at such points to such coiled .wire'structures, each having a constricting member on eachend thereof, and swedging said members on each end of such coiled wire structures to form end fittings.

18. The method of binding an intermediate portion of a continuous helically coiled stranded structure which includes the step of wrapping a metal strip helically about said structure and preforming the strip as it is being wrapped about -such structure so that it will hug such structure closely. 1

19. The method of bindingthe end of a helically coiled stranded wire structure which includes the step of wrapping said end with a metal strip of sufficient inherent strength to prevent uncoiling of said structure and in preforming said strip as it is being wrapped about the structure so that it will hug said structure closely.

20. The method of binding an end of a coiled helically about the end of said 3 wire layers, the convolutions of the outerlayer being spaced, which includes the steps of wrapping a metal striphelically about an end of the structure and in contouring said strip to fit between the convolutions of both layers.

22. The method of binding an end of a coiled wire structure comprising inner and outer layers of coiled wire, the convolutions of the outer layer being spaced, which includes the steps of wraplayer and in contouring ping a metal strip helically about an end of the structure between the convolutions of said outer the inner face of said strip to fit on and between the convolution; ofsaid inner layer.

23. The method of binding an end of a coiled wire structure comprising inner and outer layers of coiled wire structures, the convoluticns of the 5 outer layer being spaced, which includes the steps of compacting an attachment member into the Spaces between the convolution: of the inner and outer layers, and impacting the convolutions of the outer layer into the spaces between the 5 conyolutions of the inner layer.

0'1'1'0 J. BRA'IZ. 

